• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1996.06a
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• pp.153-158
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• 1996

Delay and jitter are critical factors in the real-time video services over ATM network. Mostly, delay and jitter problem are generated in input buffer when video are multiplexed. In this paper, we analyze delay and jitter of input buffer, and consider efficient control and flexible bandwidth allocation of video traffic. Also, we analyze decision of buffer size related maximum allowable delay.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.2 no.2
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• pp.181-186
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• 1998

This paper presents multiplexing structures to provide various subscriber interfaces in an ATM switching system with a high speed internal link, and analyzes the schemes in terms of a mean cell delay and a buffer sin. And we proposed a buffer management strategy to minimize a cell loss and accommodate new ATM transfer capabilities.

• Journal of KIISE
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• v.43 no.3
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• pp.327-335
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• 2016

In this paper, we propose a buffer management scheme suitable for interactive multimedia services. We consider a typical delay optimization environment so that receiver buffer lengths vary according to the round trip time estimation. In this environment, we propose an optimization technique for minimizing the loss of information that may occur when a reduced buffer length forces I/P/B frames in the buffer to drop. We modeled our problem as a Knapsack Problem for which we used dynamic programing in order to find an approximate solution. The proposed technique is compared with the existing buffer management techniques. Through simulation studies, we found that our approach could increase PSNR, which is important to video quality.

• Journal of KIISE:Information Networking
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• v.28 no.2
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• pp.242-250
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• 2001

This paper deals with the TCP bandwidth guarantee problem in a differentiated serviccs(Diffserv) network. The Diffserv assured s<:rvice differentiates packet drop probabilities to guarantee the promised bandwidth even under network congestion. However a token buffer marker fails to show adequate performance because TCI' generates packets according to the unique Tel' congestion control mechanism. We propose a marker that uses a data buffer as well as a token buffer. The marker with a data buffer works well with the assured service mechanism because it smooths Tel' traffic. We showed that the marker with a data buffer achieves the target throughput better than a marker with a token buffer only. We also showed that the optimal buffer size is proportional to reserved throughput and HTT.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.05a
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• pp.712-713
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• 2011

In this paper, the AMBA AXI slave unit that can verify the pipelined arithmetic unit is proposed and the 2-stage 16-bit pipelined multiplier is introduced as design example. The proposed AXI slave unit consists of input buffer block memory, control registers, pipelined arithmetic unit, control unit, output buffer block memory, and AXI slave interface unit. The main operational procedures are divided into the following steps, such as burst-mode input data loading for the input buffer memory, programming of control registers, arithmetic operations for block data in the input buffer memory, and burst-mode output data unloading from output buffer memory to host processor. Because the proposed AXI slave unit is general structure, it can be efficiently applicable to AMBA AXI and AHB slave unit with pipelined arithmetic unit.

• The KIPS Transactions:PartC
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• v.9C no.4
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• pp.453-458
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• 2002

Recently, the number of hacking, that use buffer overflow vulnerabilities, are increasing. Although the buffer overflow Problem has been known for a long time, for the following reasons, it continuos to present a serious security threat. There are three defense method of buffer overflow attack. First, allow overwrite but do not allow unauthorized change of control flow. Second, do not allow overwriting at all. Third, allow change of control flow, but prevents execution of injected code. This paper is for allowing overwrites but do not allow unauthorized change of control flow which is the solution of extending compiler. The previous defense method has two defects. First, a program company with overhead because it do much thing before than applying for the method In execution of process. Second, each time function returns, it store return address in reserved memory created by compiler. This cause waste of memory too much. The new proposed method is to extend compiler, by processing after compiling and linking time. To complement these defects, we can reduce things to do in execution time. By processing additional steps after compile/linking time and before execution time. We can reduce overhead.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.94-97
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• 1999

In this paper, a new real-time neural network connection admission controller is proposed. The proposed controller measures traffic flows, cell loss rate and cell delay periodically each classes. The Neural network learns the relation between those measured information and service quality by real-time. Also the proposed controller uses the DWRR multiplexer with buffer dedicated to every traffic source in order to measure the delay that cells experience in buffer. Experimental result shows that the proposed method can control effectively heterogeneous traffic sources with diverse QoS requirement.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.1041-1044
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• 1999

This paper propose a solution to resolve data overflow or leakage when a subscriber receive data to service provider. The set-top box can communicate with a service provider and can inform the service provider its data overflow or leakage. When service provider received this control signal, it changes data transmit rate and transmits data with changed rate. The buffer of set-top box is important because incoming data from a service provider are stored by it.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 1994.11a
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• pp.193-202
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• 1994

In this paper, we investigate possible scrambling methods for the JPEG(Joint Photographic Export Group) still image compression standard. In particular, we compare the conventional line rotation and line permutation methods to the DCT block scrambling in terms of the number of bits to be increased and the easiness of buffer control. Computer simulation results show that the DCT block scrambling method is suitable for both data security and buffer control in one-chip JPEG applications.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.1
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• pp.45-54
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• 2008

A new proposed repository has a final capacity of 800,000 drums radioactive waste. Most of foreign repositories have a general practice of segregating control zones which mainly contributes to classification of degree of control, whether it is called buffer zone or not. Domestic regulatory requirements of establishment of buffer zone in a repository are not much different from those of nuclear power plants for operation period, in which satisfactory design objective or performance objective is the most important factor in determination of the buffer zone. The meaning of buffer zone after closure is a minimum requested area which can prevent inadvertant intruders from leading to non-allowable exposure during institutional control period. Safety assessment with drinking well scenario giving rise to the highest probability of exposure among the intruder's actions can verify fulfillment of the buffer zone which is determined by operational safety of the repository. At present. for the repository to be constructed in a few years, the same procedure and concept as described in this paper are applied that can satisfy regulatory requirements and radiological safety as well. However, the capacity of the repository will be stepwise extended upto 800,000 drums, consequently its layout will be varied too. Timely considerations will be necessary for current boundary of the buffer zone which has been established on the basis of 100,000 drums disposal.